We are a supply center, and the only "living" thing we sell is sod. While we sell the usual for a supply center (soil, sand, rock, etc), we have also added decorative concrete and a gift shop. Anything yard related (but nothing we can kill!) to separate people from their hard earned money!

My brother manages a Landscape center. And the only live plants they sell are for in ponds.
90% of their products are concrete/brick products and bulk material. And they do very very very well.
10% is pond equipment, kits, etc